To Switch or Not To Switch: Understanding Social Influence in Recommender Systems

To investigate whether online recommendations can sway peoples' own opinions, we designed and ran an experiment to test how often people's choices are reversed by others' preferences when facing different levels of confirmation and conformity pressures. In our experiment participants were first asked to provide their preferences between pairs of items. They were then asked to make second choices about the same pairs with knowledge of others' preferences. To measure the pressure to confirm people's own opinions, we manipulated the time before the participants needed to make their second decisions. And to determine the effects of social pressure we manipulated the ratio of opposing opinions that the participants saw when making the second decision. Additionally, we tested whether other factors (i.e. age, gender and decision time) affect the tendency to revert. Our results show that others people's opinions significantly sway people's own choices. The influence is stronger when people are required to make their second decision sometime later (22.4%) than immediately (14.1%). Moreover, people are most likely to reverse their choices when facing a moderate number of opposing opinions. Finally, the time people spend making the first decision significantly predicts whether they will reverse their decisions later on, while demographics such as age and gender do not.